Authorities have arrested a man who sexually assaulted a mentally ill woman on a Los Angeles County Metro bus Wednesday. They followed a tip that came in after local TV news displayed the suspect’s picture. The tip led police straight to his house.

Los Angeles County Sheriff’s detectives arrested Kerry Trotter, 20, at his South Los Angeles home early Friday morning on suspicion of forcible rape. Jail records indicate that his bail is $1,000,000.

Authorities say he attacked the 18-year old woman around 5 p.m. while riding the 217 Metro bus line, which was not very crowded at the time.

Sgt. Dan Scott said the woman did not scream or say anything out loud during the attack and there was no fight.

“So unless you were close up or watching you may not know what he’s doing and you may think that two people are just interacting or whatever,” Scott said.

The woman reported the rape to the bus driver after the suspect got off at a stop near Sepulveda Blvd. and Slauson Blvd. Scott said detectives on the investigation believe the bus driver didn’t know the assault had happened, and immediately called dispatch when the woman reported it.

A Metro representative said transit drivers have a silent alarm they can activate to call law enforcement or a supervisor to the bus if they are aware of crime taking place. They can also call dispatch directly to report non-life threatening incidents.

Scott said it doesn’t appear that the suspect and the woman knew one another. He said the person who called in the tip wasn’t a passenger on the bus, but the relationship between the tipster and the suspect is unclear.

Scott advised riders who travel alone to sit near the front of the bus - not where it’s hard for the driver or other passengers to see you.

“This shows you that even on a public bus, which is a safe mode of transportation, something like this can happen,” he said.